Download of PhotoGrok 2.39 for Mac was available from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. This free Mac app is a product of Phil Harvey's. The application belongs to System Tools.
From the developer:
PhotoGrok categorizes photos and other files by metadata (and a whole lot more). By default, PhotoGrok will use the ExifTool tag "FileType" to build the tree. If you want to see a different tree structure, open the "Tree Tags" dialog and enter a comma-delimited list of ExifTool tags.
You may want to check out more Mac applications, such as eps2pdf, DisCatalogMaker or FindAnyFile, which might be similar to PhotoGrok.